Cylinder head temperature gauge Options

[Geezer914]

VDO no longer makes them, any other gauges out there?

[FlacaProductions]

as i understand it - and i could be wrong - non-temperature compensated gauges will read out higher as the ambient temperature goes up and lower as it goes down. ie: if your engine temp is (for example) 250 at 72 degrees, a non-compensated display will show 260 at 82.

temp-compensated will show 250 no matter the ambient temp.

[barefoot]

as i understand it - and i could be wrong - non-temperature compensated gauges will read out higher as the ambient temperature goes up and lower as it goes down. ie: if your engine temp is (for example) 250 at 72 degrees, a non-compensated display will show 260 at 82.

temp-compensated will show 250 no matter the ambient temp.

Not true, sorry.

Thermocouple based cylinder head temperature gauges use a bimetal construction that generates a voltage if one end is heated (or cooled). Thermocoulpes will measure the temperature DIFFERENCE between the hot end and the other end. Cold junction compensation introduces a measurement at the cold end then does an addition to read the actual temperature at the hot end, not just the difference.
i verified mine by placing the hot end in ~ boiling water as a bench test and got 210 degrees. Cooled to room temperature and the gauge read 73, so i know I'm reading actual head temps.
Hope this helps